Download the package from Check_MK exchange: http://exchange.check-mk.org/index.php?option=com_remository&Itemid=53&func=fileinfo&id=132
On Check_MK server:
check_mk -P install synology-nas-1.0.mkp
Add the 3 available checks to the FQDN/IP of the Synology:
check_mk --checks synology_disks -I synology.mngt.bh.helux.nl check_mk --checks synology_raids -I synology.mngt.bh.helux.nl check_mk --checks synology_system -I synology.mngt.bh.helux.nl